EP0594458B1 - Détection d'interférences entre cellules par annulation des événements de corruption de données transmis par les stations mobiles - Google Patents

Détection d'interférences entre cellules par annulation des événements de corruption de données transmis par les stations mobiles Download PDF

Info

Publication number
EP0594458B1
EP0594458B1 EP93308443A EP93308443A EP0594458B1 EP 0594458 B1 EP0594458 B1 EP 0594458B1 EP 93308443 A EP93308443 A EP 93308443A EP 93308443 A EP93308443 A EP 93308443A EP 0594458 B1 EP0594458 B1 EP 0594458B1
Authority
EP
European Patent Office
Prior art keywords
frame
control message
link control
link
base station
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP93308443A
Other languages
German (de)
English (en)
Other versions
EP0594458A3 (en
EP0594458A2 (fr
Inventor
Masashi c/o NEC Comm. Systems Ltd. Fujita
Toshitaro c/o NEC Comm. Systems Ltd. Harada
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Publication of EP0594458A2 publication Critical patent/EP0594458A2/fr
Publication of EP0594458A3 publication Critical patent/EP0594458A3/en
Application granted granted Critical
Publication of EP0594458B1 publication Critical patent/EP0594458B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0026—Transmission of channel quality indication
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
    • H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
    • H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
    • H04L1/1867—Arrangements specially adapted for the transmitter end
    • H04L1/1874—Buffer management

Definitions

  • the present invention relates generally to TDMA (time division multiple access) cellular mobile communication systems, and more specifically to a technique for detecting interference affecting the up-link control channel of a TDMA cellular mobile communication system when the control channel carries no signaling message.
  • TDMA time division multiple access
  • interference that occurs on the up-link control channel (for transmission from mobiles to cell-site base station) from adjacent cells in the absence of a control message from mobile stations is detected at the base station and counted at intervals and reported to the management center for evaluation.
  • the current method of interference detection involves the evaluation of the quality of signals received on the up-link control channel.
  • data corruption occurs when more than one mobile station simultaneously transmits a control message. Due to the inability of the base station to make a distinction between inter-cellular interference and intra-cellular interference, the base station recognizes such a simultaneous transmission as an inter-cellular interference event. Therefore, the current method is not satisfactory to obtain a precision interference count.
  • the object of this invention is achieved by canceling data corruption events caused by collision between mobile stations from the list of inter-cellular interference events which have been detected on the up-link control channel carrying no control messages.
  • the base station In a TDMA communication system where a base station and mobile stations establish up-link frames for transmission of signals in a direction from the mobile stations to the base station and down-link frames for transmission of signals in a direction from the base station to the mobile stations, the base station includes a frame status memory and each of the mobile station includes a collision memory.
  • each mobile station transmits an up-link control message on one of the up-link frames when it is available for all the mobile stations.
  • the base station determines whether the quality of the received up-link control message is affected during transmission.
  • a corruption status indication is stored into a position of the frame status memory which corresponds to the up-link frame on which the control message is transmitted if the quality is determined to be affected.
  • the base station detects a frame identification contained in the received up-link control message, it erases a corruption status indication stored in a position of the frame status memory identified by the detected frame identification.
  • the base station transmits a down-link control message on one of the down-link frames, containing an indication whether the quality of the received up-link control message is determined as being affected or not during transmission.
  • the mobile station On receiving the down-link control message, the mobile station examines the indication contained therein. If it indicates that the quality of the up-link control message is determined as being affected, the frame identification of the up-link frame is stored into the collision memory, and a copy of the transmitted up-link control message is retransmitted, containing a copy of the stored frame identification. In this way, a corruption status indication stored in the frame status memory during the previous data collision event is erased by a report from the mobile station. If the second transmission should fail, the retransmission process is repeated until an indication is given that the quality of the up-link control message is determined as being unaffected.
  • the corruption status indications stored in the frame status memory are counted to produce an inter-cellular interference count.
  • a schematic block diagram of a cell-site base station of a time division multiple access (TDMA) cellular mobile communication system includes a multiplexer 101 for receiving a down-link time-division multiplex (TDM) signal via a land-line 122 from a mobile telephone switching office 120 which is in turn connected by trunks 121 to the public switched telephone network, not shown.
  • Multiplexer 101 combines the incoming TDM signal with a signaling message from the cell-site controller 106 so that it is inserted into the control slot (i.e., down-link control channel) of a down-link frame.
  • TDM time-division multiplex
  • the controller 106 is connected via control lines 124 to the MTSO 120 to exchange signaling messages.
  • the output of multiplexer 101 is applied to a modulator 102 where it is modulated upon a carrier and supplied to a transceiver 103 for amplification and transmission to mobile stations.
  • Signals from mobile stations are transmitted on appropriate time slots of an up-link frame if an idle indication is given by the control slot of a previous up-link frame, and received by transceiver 103 where it is amplified and then converted by a demodulator 104 to a baseband signal for coupling to a demultiplexer 105 .
  • Signaling messages, such as call-setup signals, from mobile stations are separated by demultiplexer 105 from information signals and supplied to the controller 106 and an out-of-sync detector 107 which provides an output signal to the controller 106 when it detects an out-of-sync condition of a received control message when interference occurs.
  • the information signals from demultiplexer 105 are transmitted via a land-line 123 to the MTSO 120 as an up-link TDM signal.
  • a frame status memory 108 is connected to the controller 106 .
  • the memory 108 has a plurality of storage locations corresponding respectively to up-link frames starting with frame #1 to frame #N to store a bit "0" in each location if a data corruption is not detected in the corresponding frame by the controller 106 and store a bit "1" if a data corruption is detected.
  • the controller 106 reads frame status data from memory 108 at intervals, and reports the number of interferences to the MTSO 120 .
  • each mobile station receives down-link frames from the base station 100 through a transceiver 200 .
  • the received frames are demodulated to baseband frame signals by a demodulator 201 and applied to a time-slot detector 202 where the message addressed to the mobile station is detected.
  • the output of time-slot detector 202 is coupled to a digital-to-analog converter 203 in which it is converted to an analog signal and supplied to a speech circuit 204 for coupling to the handset 205 .
  • Signals from the handset are coupled through the speech circuit 204 to an analog-to-digital converter 206 where it is converted to a digital signal and coupled to a modulator 207 for conversion to the up-link frequency for transmission through the transceiver 200 .
  • a controller 208 provides an overall control of the mobile station by receiving a call-request signal from the handset 205 to generate a signaling message and stores it in a buffer 209 whose output is connected to the input of modulator 207 and receiving control channel data from time-slot detector 202 to determine whether the next up-link frame is busy or idle, and determine whether a previously sent message is properly received or not by the base station 100 .
  • the effect of the buffer 209 is to produce a copy of the signaling message for retransmission if a previously transmitted signal is corrupted by data collision.
  • the controller 208 enables the buffer 209 to transmit the stored message if a previous transmission is found to be futile and directs it to discard the stored message if the previous transmission is found to be properly received by the base station.
  • a collision memory 210 connected to the controller 208 .
  • the memory 209 has a plurality of storage locations, one of which is used for storing a collision count "C" indicating the number of data collisions encountered in sequence and the remainder for storing frame numbers identifying the frames where data collision has occurred.
  • Controller 208 constantly reads data from the collision memory 209 and transmits it on an up-link control channel together with a signaling message.
  • Each down-link frame includes, for example, two information slots and a control slot containg a signaling message, an idle/busy (I/B) field, a receive/not receive (R/N) field and a partial echo (PE) field as shown in Fig. 5.
  • I/B idle/busy
  • R/N receive/not receive
  • PE partial echo
  • FIG. 3 A flowchart of a program for the controller 106 is shown in Fig. 3 for controlling the base station.
  • Program execution starts with action step 300 which clears the contents of the frame status memory 108 by resetting them to all zero's.
  • a report interval timer is started for defining intervals at which the controller 106 produces an inter-cellular interference count report.
  • the controller 106 checks to see if a signaling message is received on a frame "k". If the answer is negative, control branches to step 318 to set an idle indication to the I/B field, a "not-receive" indication to the R/N field, and all zero's into the PE field.
  • step 314 Exit then is to step 314 to transmit the next down-link frame, and control exits to decision step 315 to check to see if the period of the timer has expired. If not, control returns to decision step 302 . It is seen that when there is no signal from mobile stations, an idle indication is given to give a chance to all mobile stations to access the next frame for transmission of a control message.
  • the varialble S k is likewise set to 1, and will be subsequently reset to 0 in response to a report from one of the contending mobile stations.
  • Step 318 follows to set the contents of the control slot in the same manner as in the absence of signal from mobile stations and the next frame is transmitted at step 314 as described above. If the signal quality is determined to be acceptable at step 303 , control branches to step 304 to examine the collision report field of the up-link control channel and determine if the collision count "C" is equal to zero or equal to or greater than 1.
  • the I/B field is forcibly set to "idle" state to allow all mobile stations to gain access to the up-link control channel on the #1 frame of the next multiframe.
  • the base station transmits the next down-link frame.
  • the timer is then checked at step 315 to determine if the timeout period for making a collision report has expired. If the answer is negative, control returns to step 302 to repeat the above process.
  • the frame status memory 108 is updated with a list of the collision report containing at least one collision frame number.
  • a collision frame variable j to set equal to 1 at step 305 to access the storage location of the frame status memory 108 that corresponds to the frame number of the first entry of the collision list.
  • Control moves to decision step 306 to determine if the frame position status S j of that storage location is equal to 1.
  • FIG. 4 A flowchart of a program for the controller 208 of each mobile station is shown in Fig. 4.
  • Program execution starts with action step 400 which clears the contents of the collision memory 210 by resetting them to all zero's.
  • the I/B field of the control channel of a received down-link frame is examined at step 402 . If an idle indication is given by the I/B field, control branches to step 403 to transmit the control message on the control channel of a subsequent up-link frame "k" from the buffer 209 , and keep a copy of the transmitted signal in the buffer.
  • step 404 examine the R/N field of the received control channel to see if an "receive" or "not receive” indication is given.
  • the up-link control channel contains a collision field which is a copy of the collision memory 210 . Initially, the collision count C is set to 0 and no frame number is set in the collision field of the transmitted control message.
  • step 408 If an out-of-sync condition is detected by detector 107 upon transmission of a control message from a mobile station, a "not receive" indication is set into the R/N field, and the mobile station recognizes that the previous message was corrupted by data collision with another mobile station which is either located within the same or adjacent cell zone, and control proceeds to step 408 to increment the collision count value "C" of collision memory 210 by 1 and store into the first entry of the frame number locations of memory 210 the identification number of the frame on which the previous control message was sent. Exit then is to step 409 to introduce a random delay time and then control moves to step 410 to examine the I/B field of a down-link frame which is received following the random delay time.
  • step 410 If idle indication is given at step 410, control proceeds to step 411 to transmit the stored copy of the transmitted message from the buffer 209 on an up-link control channel of the next up-link frame, containing a collision field in which the collision count C is set to 0 and no frame number is set. Following the retransmission of the previous message, control returns to step 404 .
  • Step 405 If the comparison of the PE field at step 405 reveals that there is a substantial mismatch between the copy of partial data returned from the base station and the corresponding part of the stored data, the mobile station recognizes that a data collision occurred on the previous frame, and control branches to step 408 to increment the collision count value "C" of collision memory 210 by 1 and store the frame number of the frame on which the previous control message was sent into the first entry of the frame number locations of memory 210 .
  • Steps 409 to 411 are executed to transmit a copy of the previous message containing a collision field in which the collision count C is set to 1 and the frame number of the previous frame is set.
  • mobile station #2 sends a message and encounters a data collision with a signal from an adjacent cell.
  • frame #2 is the only frame where interference has occurred, whereas in the prior art interference detection technique frames #3 and #6 also are counted.
  • the above process is repeated during the period of the timer and the number of interference-affected frames is determined (step 316 ) and reported to the MTSO 120 where the report is collected and analyzed to determine the radio interference ratio of the system. Since data collision is excluded from the report, the radio interference ratio of the control channel of a TDMA cellular mobile communication system can be precisely determined.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Mobile Radio Communication Systems (AREA)

Claims (4)

  1. Système de communication, comportant une station de base et une pluralité de stations mobiles, ladite station de base et lesdites stations mobiles établissant des trames de liaison montante pour l'émission de signaux des stations mobiles vers la station de base et des trames de liaison descendante pour l'émission de signaux de la station de base vers les stations mobiles, ladite station de base (100) comprenant :
    des moyens pour recevoir un message de commande de liaison montante sur l'une desdites trames de liaison montante ;
    une mémoire d'état de trame (108) ;
    des moyens (107, 106) pour déterminer si la qualité du message de commande de liaison montante reçu est affectée au cours de l'émission, et pour mémoriser une indication d'état de corruption en une position de ladite mémoire d'état de trame correspondant à ladite trame de liaison montante si la qualité est déterminée comme ayant été affectée ;
    des moyens pour détecter une identification de trame à partir du message de commande de liaison montante reçu et pour effacer une indication d'état de corruption mémorisée en une position de la mémoire d'état de trame correspondant à l'identification de trame détectée ; et
    des moyens pour émettre un message de commande de liaison descendante sur l'une d'une pluralité de trames de liaison descendante, le message de commande de liaison descendante émis indiquant si la qualité du message de commande de liaison montante reçu est déterminée comme ayant été affectée ;
       chacune desdites stations mobiles (figure 2) comprenant :
    des moyens pour émettre un message de commande de liaison montante sur l'une desdites trames de liaison montante lorsque ladite trame de liaison montante est utilisable par l'ensemble des stations mobiles ;
    des moyens pour recevoir ledit message de commande de liaison descendante ;
    des moyens pour amener lesdits moyens d'émission à réémettre une copie du message de commande de liaison montante si le message de commande de liaison descendante reçu indique que la qualité du message de commande de liaison montante est déterminée comme ayant été affectée au cours de l'émission ;
    une mémoire de collision (210) , et
    des moyens, sensibles au message de commande de liaison descendante reçu indiquant que la qualité du message de commande de liaison montante est déterminée comme ayant été affectée, pour mémoriser l'identification de trame de ladite trame de liaison montante dans ladite mémoire de collision, et pour amener lesdits moyens d'émission à réémettre une copie du message de commande de liaison montante émis contenant une copie de l'identification de trame mémorisée.
  2. Système de communication selon la revendication 1, dans lequel ladite station de base (100) est connectée à un réseau téléphonique commuté (121) et inclut des moyens pour compter les indications d'état de corruption mémorisées dans ladite mémoire d'état de trame à des intervalles périodiques afin de produire un comptage d'interférence, et pour rapporter le comptage audit réseau.
  3. Procédé pour système de communication comportant une station de base et une pluralité de stations mobiles, dans lequel ladite station de base et lesdites stations mobiles établissent des trames de liaison montante pour l'émission de signaux des stations mobiles vers la station de base et des trames de liaison descendante pour l'émission de signaux de la station de base vers les stations mobiles, ladite station de base incluant une mémoire d'état de trame et chaque dite station mobile incluant une mémoire de collision, ce procédé comprenant :
    a) l'émission, à partir d'une station mobile, d'un message de commande de liaison montante sur l'une desdites trames de liaison montante lorsque ladite trame de liaison montante est utilisable par l'ensemble des stations mobiles ;
    b) la réception, à ladite station de base, dudit message de commande de liaison montante et la détermination du fait que la qualité du message de commande de liaison montante reçu est affectée ou non au cours de l'émission ;
    c) la mémorisation d'une indication d'état de corruption en une position de ladite mémoire d'état de trame correspondant à ladite trame de liaison montante si ladite qualité est déterminée comme ayant été affectée ;
    d) la détection d'une identification de trame à partir du message de commande de liaison montante reçu et l'effacement d'une indication d'état de corruption mémorisée en une position de ladite mémoire d'état de trame identifiée par l'identification de trame détectée;
    e) l'émission, à partir de ladite station de base, d'un message de commande de liaison descendante sur l'une d'une pluralité de trames de liaison descendante, le message de commande de liaison descendante émis indiquant si la qualité du message de commande de liaison montante reçu est déterminée par l'étape (b) comme ayant été affectée au cours de l'émission ;
    f) la réception dudit message de commande de liaison descendante à ladite station mobile ; et
    g) si le message de commande de liaison descendante reçu indique que la qualité du message de commande de liaison montante est déterminée comme ayant été affectée, la mémorisation de l'identification de trame de ladite trame de liaison montante dans ladite mémoire de collision, la réémission d'une copie du message de commande de liaison montante émis contenant une copie de l'identification de trame mémorisée, et la répétition des étapes (f) et (g) jusqu'à ce que le message de commande de liaison descendante reçu indique que la qualité du message de commande de liaison montante est déterminée comme ayant été non affectée.
  4. Procédé selon la revendication 3, comprenant, en outre, le comptage des indications d'état de corruption mémorisées dans ladite mémoire d'état de trame à des intervalles périodiques afin de produire un comptage d'interférence.
EP93308443A 1992-10-23 1993-10-22 Détection d'interférences entre cellules par annulation des événements de corruption de données transmis par les stations mobiles Expired - Lifetime EP0594458B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP285651/92 1992-10-23
JP4285651A JP3012414B2 (ja) 1992-10-23 1992-10-23 制御チャネル干渉検出方式
JP28565192 1992-10-23

Publications (3)

Publication Number Publication Date
EP0594458A2 EP0594458A2 (fr) 1994-04-27
EP0594458A3 EP0594458A3 (en) 1994-09-28
EP0594458B1 true EP0594458B1 (fr) 1999-07-14

Family

ID=17694300

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93308443A Expired - Lifetime EP0594458B1 (fr) 1992-10-23 1993-10-22 Détection d'interférences entre cellules par annulation des événements de corruption de données transmis par les stations mobiles

Country Status (5)

Country Link
US (1) US5412659A (fr)
EP (1) EP0594458B1 (fr)
JP (1) JP3012414B2 (fr)
CA (1) CA2109169C (fr)
DE (1) DE69325626T2 (fr)

Families Citing this family (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2282736B (en) * 1993-05-28 1996-12-11 Nec Corp Radio base station for a mobile communications system
FI933129A0 (fi) * 1993-07-08 1993-07-08 Nokia Mobile Phones Ltd Dataoeverfoeringsfoerfarande foer ett digitalt cellulaert mobiltelefonsystem och ett digitalt cellulaert mobiltelefonsystem
DE69432960T2 (de) * 1993-11-01 2004-03-04 Telefonaktiebolaget Lm Ericsson Übertragung im ARQ-Modus, bei der eine Basisstation den Status der an eine Mobilstation übertragenen Rahmen bestimmt
FI97671C (fi) * 1994-02-14 1997-01-27 Nokia Telecommunications Oy Menetelmä merkinantosanomien käsittelemiseksi matkaviestinjärjestelmässä ja matkaviestinjärjestelmä
CN1128093A (zh) * 1994-03-18 1996-07-31 菲利浦电子有限公司 以扩频为基础的蜂窝移动无线系统和控制装置，无线基站和无线移动站
US5657326A (en) * 1994-12-20 1997-08-12 3Com Corporation Radio based collision detection for wireless communication system
US5745479A (en) * 1995-02-24 1998-04-28 3Com Corporation Error detection in a wireless LAN environment
JP2919293B2 (ja) * 1995-03-02 1999-07-12 日本電気株式会社 パケット通信方式
JP2746183B2 (ja) * 1995-04-04 1998-04-28 日本電気株式会社 多重アクセス方法
ZA965340B (en) * 1995-06-30 1997-01-27 Interdigital Tech Corp Code division multiple access (cdma) communication system
WO1997015163A1 (fr) * 1995-10-18 1997-04-24 Telefonaktiebolaget Lm Ericsson Procede ameliore d'attribution de canaux
DE69739589D1 (de) * 1996-12-26 2009-10-29 Nippon Telegraph & Telephone Verfahren und Schaltung zur Rahmensynchronisierung
RU2126591C1 (ru) * 1997-06-16 1999-02-20 Закрытое акционерное общество "МобиКом" Система сотовой подвижной связи
US6038223A (en) * 1997-10-22 2000-03-14 Telefonaktiebolaget Lm Ericsson (Publ) Access scheme for packet data in a digital cellular communication system
JP3968514B2 (ja) * 2002-07-05 2007-08-29 ソニー株式会社 無線通信システム、無線通信装置及び無線通信方法、並びにコンピュータ・プログラム
JP4705808B2 (ja) * 2005-05-18 2011-06-22 株式会社日立製作所 無線通信システム、これを構成する無線中継装置及び無線通信端末、無線通信方法
JP2009194581A (ja) * 2008-02-14 2009-08-27 Nec Corp フレーム復元方法、フレーム復元回路及びフレーム復元プログラム
KR101499375B1 (ko) * 2011-02-25 2015-03-05 미쓰비시덴키 가부시키가이샤 제어 장치, 제어 시스템 및 통신 방법
EP4214984B1 (fr) 2020-09-18 2024-10-09 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Système de communication

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS623536A (ja) * 1985-06-29 1987-01-09 Oki Electric Ind Co Ltd 移動体データ通信の良否判定装置
DE3607687A1 (de) * 1986-03-08 1987-09-10 Philips Patentverwaltung Verfahren und schaltungsanordnung zum weiterschalten einer funkverbindung in eine andere funkzelle eines digitalen funkuebertragungssystems
US5042082A (en) * 1989-06-26 1991-08-20 Telefonaktiebolaget L. M. Ericsson Mobile assisted handoff
JP2733110B2 (ja) * 1989-09-19 1998-03-30 日本電信電話株式会社 無線信号伝送方式
US5159593A (en) * 1990-07-02 1992-10-27 Motorola, Inc. Channel acquistion and handoff method and apparatus for a TDMA communication system
US5257399A (en) * 1990-11-28 1993-10-26 Telefonaktiebolaget L M Ericsson Multiple access handling in a cellular communications system
US5175867A (en) * 1991-03-15 1992-12-29 Telefonaktiebolaget L M Ericsson Neighbor-assisted handoff in a cellular communications system

Also Published As

Publication number Publication date
JP3012414B2 (ja) 2000-02-21
CA2109169C (fr) 1999-03-09
JPH06141362A (ja) 1994-05-20
EP0594458A3 (en) 1994-09-28
EP0594458A2 (fr) 1994-04-27
DE69325626D1 (de) 1999-08-19
US5412659A (en) 1995-05-02
CA2109169A1 (fr) 1994-04-24
DE69325626T2 (de) 1999-11-04

Similar Documents

Publication Publication Date Title
EP0594458B1 (fr) Détection d'interférences entre cellules par annulation des événements de corruption de données transmis par les stations mobiles
EP0619664B1 (fr) Système de communication par satellite à accès aléatoire employant des nombres aléatoires générés dans un domaine variable avec le trafic dans le canal
AU710896B2 (en) Method and apparatus for dynamically selecting the length of mobile station burst communications on the reverse digital control channel
US5481539A (en) Datagram communication service over a cellular telephone network
EP0523648B1 (fr) Système de communication de données à accès aléatoire avec possibilité d'attribution d'intervalle temporel à des utilisateurs concurrents
US4866788A (en) Process for controlling retransmission of messages from transmitting stations belonging to a cellular system
EP0689303A1 (fr) Système de communication mobile TDMA avec communication simultanée entre base et mobiles à une première fréquence et entre mobiles à une seconde
US5113413A (en) Voter arrangement for multiple site PST RF trunking system
US5131010A (en) Voice guard digital voter for multiple site PST RF trunking system
US20010046877A1 (en) Multicast signal transmission power control method and base station using the same
KR920011113A (ko) 셀 통신 시스템에서의 다중 액세스 방법 및 장치
CA2068009C (fr) Systeme permettant de decentraliser des fonctions de commande de reseau en sens montant et de reduire au minimum les ressources necessaires a l'evaluation du niveau de puissance des stations dans un reseau de transmission de donnees rf
EP0802696B1 (fr) Procede de commande de retransmission pour communications mobiles amdc
KR100271748B1 (ko) 양방향 메세징 시스템에서 발신 메세지를 전송하기 위한 방법및 장치
US7043196B1 (en) Method and apparatus for transmitting data
EP1362436B1 (fr) Repeteur intelligent et procede permettant d'obtenir une signalisation amelioree
US6819676B1 (en) Method for improving scheduling fairness of signal transmission/reception in a network
EP0695101B1 (fr) Systeme mobile de radiocommunication et recepteur radio
US6035206A (en) Method and apparatus for transmitting multiple communication messages on a communication resource
EP0860061B1 (fr) Telephonie numerique utilisant des messages de commande transmis en tranches de temps pour l'attribution de frequences h.f.
Cleary et al. An investigation of reservation random access algorithms for voice-data integration in microcellular wireless environments
Willig et al. PRIOREL-COMB: A protocol framework supporting relaying and packet combining forwireless industrial networking
Chua Performance modelling of an idle-signal casting multiple access with failure detection (ICMA/FD) mobile PRLAN
CA2034369C (fr) Montage de vote ameliore pour circuits de communication rf pst
Cleary et al. Voice-data integrated channel access for microcellular networks using splitting RRA algorithms

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB

17P Request for examination filed

Effective date: 19940911

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 19980819

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69325626

Country of ref document: DE

Date of ref document: 19990819

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20101020

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20101020

Year of fee payment: 18

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20111103

Year of fee payment: 19

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20121022

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20130628

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20121022

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20130501

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69325626

Country of ref document: DE

Effective date: 20130501

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20121031